Modern contraceptives not only play a critical role in preventing unplanned pregnancy but also contribute to a woman?s well-being by empowering her with the necessary resources to control her own reproductive health. However, currently available female contraceptives are lacking in one or more important parameters, including effectiveness, safety, and usability, thus rendering the currently available contraceptive mix sub-optimal. A high impact driver of the growing contraceptives market is the number of unintended pregnancies, the risk of which is increased when contraceptives are used incorrectly, inconsistently, or not at all. Approximately 1.9 million unintended pregnancies were reported in the US in 2016, posing a significant medical risk for mothers and children, and placing significant economic burdens on individual women and the general public. Imperfect use of currently available contraceptive options can be attributed to a range of obstacles, including inconvenience (daily action, or action at the time of intercourse) and adverse side effects associated with hormonal contraceptives. These drawbacks demonstrate a need for novel, non-hormonal contraceptive options that are convenient, easy-to-use, and effective. To meet this need, Dar Bioscience, Inc. is developing the Ovaprene device, a non-hormonal intravaginal ring that provides a safe and effective monthly birth control option. Ovaprene combines a flexible mesh barrier that covers the cervix while slowly releasing a mix of non-hormonal, spermiostatic ingredients. The FDA has already designated Ovaprene as a combination product and determined that the Center for Devices and Radiological Health (CDRH) will be the lead reviewing agency for this novel contraceptive. The objective of this SBIR proposal is to demonstrate the preliminary contraceptive performance, safety, active agent release profile, acceptance, and fit of Ovaprene in a single-center, open-label, non-significant risk device study. Preliminary efficacy will be evaluated by postcoital testing and the measurement of any progressively motile sperm gaining access to the cervix in women wearing the Ovaprene device. Safety will be evaluated over 28 days of continuous use. We will also establish post-production quality control metrics and collect agent release data. The successful accomplishment of all milestones in this proposal will provide necessary information to support a Pivotal efficacy human study of Ovaprene contraceptive effectiveness in advance of FDA clearance for the US market.